// Copyright (C) 2002-2008 Nikolaus Gebhardt
// This file is part of the "Irrlicht Engine".
// For conditions of distribution and use, see copyright notice in irrlicht.h

#ifndef __I_READ_FILE_H_INCLUDED__
#define __I_READ_FILE_H_INCLUDED__

#include "IReferenceCounted.h"

namespace irr
{
namespace io
{

	//! Interface providing read acess to a file.
	class IReadFile : public virtual IReferenceCounted
	{
	public:
		//! Destructor
		virtual ~IReadFile() {}

		//! Reads an amount of bytes from the file.
		/** \param buffer Pointer to buffer where to read bytes will be written to.
		\param sizeToRead Amount of bytes to read from the file.
		\return How much bytes were read. */
		virtual s32 read(void* buffer, u32 sizeToRead) = 0;

		//! Changes position in file
		/** \param finalPos: Destination position in the file.
		\param relativeMovement: If set to true, the position in the file is
		changed relative to current position. Otherwise the position is changed
		from beginning of file.
		\return True if successful, otherwise false. */
		virtual bool seek(long finalPos, bool relativeMovement = false) = 0;

		//! Get size of file.
		/** \return Size of the file in bytes. */
		virtual long getSize() const = 0;

		//! Get the current position in the file.
		/** \return Current position in the file in bytes. */
		virtual long getPos() const = 0;

		//! Get name of file.
		/** \return File name as zero terminated character string. */
		virtual const c8* getFileName() const = 0;
	};

	//! Internal function, please do not use.
	IReadFile* createReadFile(const c8* fileName);
	//! Internal function, please do not use.
	IReadFile* createLimitReadFile(const c8* fileName, IReadFile* alreadyOpenedFile, long areaSize);
	//! Internal function, please do not use.
	IReadFile* createMemoryReadFile(void* memory, long size, const c8* fileName, bool deleteMemoryWhenDropped);

} // end namespace io
} // end namespace irr

#endif

